In plain words
‘Ahaṃ brahmāsmi’, I myself am Brahman: this eternally true word must stay fixed for ever in man's heart. ‘Sarvaṃ khalvidaṃ brahma’: wherever you look it is Brahman alone; that very feeling, that vast feeling, pervades this world. ‘Ayamātmabrahma’: this itself is the turīya state. They likened this very state to the sound of Oṃkāra. This Oṃkāra has a spelling. Just as the word ‘God’ has a spelling. In the same way, this ‘Oṃ’ too is a word made up of a few letters. ‘A, U, M’: the joining of these three letters is ‘Oṃ’. The maharṣis of those days went on teaching this to the world as the great mantra. ‘A’ is Lakṣmaṇa, ‘U’ is Bharata, ‘M’ is Śatrughna; the unity of these three, ‘Oṃ’, is Rāma. What is made up of the unity of these three is Ātmārāma. This itself is ‘ramayati iti rāmaḥ’. What is delighted in is the principle of the Ātma alone. When we enquire carefully into this word Rāma by the science of numbers, it becomes clear how much inner meaning lies in it. What is meant by nāmaṃ? ‘Na, a, ma’ = nāma; nā = 0. In the science of numbers, a = 2, ma = 5; 0 + 2 + 5 = 7. The principle of the Name of Rāma lies contained in the seven notes. The Name teaches the seven notes. It makes known the seven seas. It points to the seven ṛṣis. Calling it a saptāha, people perform the saptāha of the Name for seven days. What is the reason for this? The Name: by the saptāha, by the thought of the seven ṛṣis, by the seven colours themselves and by the seven sounds, this world stays filled. This is sa ri ga ma pa da ni: seven. In these seven letters themselves all feelings lie contained. These they have been calling the seven notes.
Made of Śabda-brahman, made of all that moves and does not move, made of light, made of speech, made of eternal Ānanda, made of That which is beyond the highest.
What is joined with the seven notes is made of That which is beyond the highest. Rā + ma: rā is 2, ma is 5; the two together make the number 7. This is what people speak of as holding a saptāha of the Name of Rāma. The number called seven is the seven notes themselves, joined with the form of God!